1. Technical Field
This invention relates to coin telephone station apparatus and more particularly to a line powered controller for a coin telephone set.
2. Description of the Prior Art
Telephone company improvement programs in the last decade have resulted in a multitude of coin service innovations which better serve customer needs and reduce operating costs. Illustratively, the programs have modified coin service from prepay to dial-tone-first operation and have provided free coin service for special numbers, such as the "911" emergency code. In addition, single slot paystations have been introduced for flexibility in deposits, improved transmission, and reductions in vandalism and theft. Such a single slot phone uses a solid state totalizer circuit which counts the coin deposits and outpulses respective tone pulses for each type of coin for facilitating more automatic coin call processing. Significantly, the introduction of TSPS (Traffic Service Position System) and its integrated ACTS (Automatic Coin Telephone System) substantially aid the more efficient and less costly serving of coin calls with significantly reduced operator assistance.
Despite the improvements achieved through the foregoing programs, telephone companies have not adequately solved the problem of reliably determining the operational state of public telephones without dispatching a repair person to the site of the telephone. Many of these telephones are remotely located in open and sometimes harsh environments. Moreover, all are not always found to be inoperative when a repair person visits. Hence, the scheduling of maintenance on coin telephones is an inefficient and costly procedure for the telephone companies.
In view of the foregoing, it is desirable to have a coin telephone set compatible with the existing telephone system by being operable with loop power from the central office, yet sophisticated enough to perform extensive operational checks which include determining if the set is fully functional before operating as a coin telephone. It is also desirable to have a telephone set that will notify the central office of its inoperable condition, yet when the failure permits, still allows for limited operation.